Henry James said this quote

It had belonged to that idea of the exasperated consciousness of his victim to become a real test for him; since he had quite put it to himself from the first that, oh distinctly! he could cultivate his whole perception. He had felt it as above all open to cultivation--which indeed was but another name for his manner of spending his time. He was bringing it on, bringing it to perfection, by practice; in consequence of which it had grown so fine that he was now aware of impressions, attestations of his general postulate, that couldn't have broken upon him at once.